The present invention relates to adapting a circuit breaker plug-in base to various circuit breaker frame sizes and more particularly to adjusting the spacing of contact jaws of a circuit breaker plug-in base.
Conventionally, a plug-in base for a circuit breaker is mounted on a panel board or other base structure and is wired to circuitry on the base structure. A circuit breaker unit is installed in the plug-in base by inserting stabs protruding from the circuit breaker unit into jaws fixed to the plug-in base. The jaw/stab connection provides the primary electrical connection between the circuit breaker unit and the plug-in base. This connection may also mechanically retain the circuit breaker in the plug-in base.
Conventionally, a plug-in base is configured for a specific circuit breaker frame size. Thus, there is a need to be able to adapt a plug-in base so as to be used with different circuit breaker frame sizes.
An object of the invention is to fulfill the need referred to above. In accordance with the principles of the present invention, this objective is achieved by a method of adjusting spacing between first and second jaw structures of a plug-in base for receiving a circuit breaker. The method includes providing a plug-in base having first and second jaw structures constructed and arranged to receive stabs of a circuit breaker. The first jaw structure is disposed in a first housing and the second jaw structure is disposed in a second housing. Each of the first and second housings has an upper surface and an opposing lower surface. A first spacer is placed between the first jaw structure and the upper or lower surface of the first housing and a second spacer is placed between the second jaw structure and the upper or lower surface of the second housing to define a certain spacing between the first and second jaw structures. The spacers are movable to different positions to change the spacing between the jaw structures.
In accordance with another aspect of the invention, a plug-in base for a receiving a circuit breaker is provided. The plug-in base includes a main body portion having first and second jaw structures constructed and arranged to receive stabs of a circuit breaker. The first jaw structure is disposed in a first housing and the second jaw structure is disposed in a second housing. Each of the first and second housings has an upper surface and an opposing lower surface. A first spacer is disposed between the first jaw structure and the upper or lower surface of the first housing. A second spacer is disposed between the second jaw structure and the upper or lower surface of the second housing. The spacers define a certain spacing between the first and second jaw structures.
Other objects, features and characteristics of the present invention, as well as the methods of operation and the functions of the related elements of the structure, the combination of parts and economics of manufacture will become more apparent upon consideration of the following detailed description and appended claims with reference to the accompanying drawings, all of which form a part of this specification.